PubMed Health⌕ Search

Biomedical subjects

S Soimakallio

Publications and source records attributed to S Soimakallio.

At least 19 recordsLinked to original sources
PubMed2006

Learning curve for add-on stereotactic core needle breast biopsy.

PURPOSE: To evaluate the learning curve for an add-on 14 G stereotactic core needle biopsy (SCNB). MATERIAL AND METHODS: A total of 231 non-palpable breast lesions that had undergone add-on SCNB were evaluated in this prospective study. Five radiologists performed their first three biopsies under supervision. Subsequent, independently performed, biopsies were also evaluated. The samples were collected in three different containers: the first sample in container A, the second and third samples in container B, and subsequent samples in container C (available for four radiologists from the first biopsy on). Technically successful biopsies and false-negative rate in three container combinations (A, A+B, A+B+C) were reported as a function of operator experience. RESULTS: Technically unsuccessful biopsies occurred significantly more often in microcalcifications than in masses (14.9% versus 3.8%; P=0.04). For microcalcifications, the rate of successful biopsies was 75% (18/24) for the first 5 biopsies and 87.8% (79/90) for the subsequent biopsies (P=0.335); rates for the masses were 95.7% (22/23) and 96.3% (79/82) (P=1.0), respectively. A tendency was noted for the false-negative rate to be higher for the first five biopsies in three container combinations than in subsequent cases. CONCLUSION: Our results support the existence of a learning curve, especially in the biopsy of microcalcifications. More than three mentor-guided biopsies are needed.

Biopsy, Needle↗
PubMed2006

ApoE polymorphism and acute stroke: a study with diffusion- and perfusion-weighted MRI and MR angiography.

OBJECTIVES: We examined whether the apolipoprotein E (ApoE) allele epsilon4 influences imaging findings in stroke as assessed by diffusion- (DWI) and perfusion-weighted (PWI) magnetic resonance imaging, and MR angiography (MRA). METHODS: Eight ApoE epsilon4 carriers and 15 non-carriers with acute ischemic stroke in the anterior circulation underwent DWI, PWI, and MRA within 24 h of stroke. DWI and PWI were repeated a week later. The apparent diffusion coefficient, relative cerebral volume (rCBV), relative cerebral blood flow (rCBF) and relative mean transit time were measured in three subregions on day one. RESULTS: In the ischemic core and the area of infarct growth, rCBV values were significantly higher in the epsilon4 carriers compared with the non-carriers. Based on the MRA findings, collateral blood flow was better in the epsilon4 carriers than in the non-carriers. Under the comparable severity of hypoperfusion, the hypoperfused area proceeded to infarction later or did not proceed to infarction at all in the non-carriers. CONCLUSION: These preliminary data suggest that in the ApoE allele epsilon4 carriers the threshold for the brain tissue to survive hypoperfusion versus to proceed to infarction seems to be different from that of the non-carriers.

Acute Disease↗
PubMed2003

Detecting the subregion proceeding to infarction in hypoperfused cerebral tissue: a study with diffusion and perfusion weighted MRI.

Diffusion and perfusion weighted MRI have been widely used in ischaemic stroke. We studied 17 patients in whom ischaemic areas showed an ischaemic core, an area of infarct growth and hypoperfused but ultimately surviving tissue. Apparent diffusion coefficients (ADC) were measured on days 1, 2, and 8 in the three subregions and in contralateral control areas. Cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) were measured in these regions on day 1 perfusion maps. On day 1, the ischaemic core had very low ADC and CBF and increased MTT. The ADC in the ischaemic core gradually increased during the week. The area of infarct growth on day 1 had slightly but significantly decreased ADC (96% of control, P=0.028), moderately decreased CBF and increased MTT. On day 1 the hypoperfused but surviving tissue had slightly but significantly increased ADC (103% of control, P=0.001), mildly decreased CBF and increased CBV and MTT. The ADC of the area of infarct growth decreased to the same level as in the ischaemic core on days 2 and 8. That of surviving tissue was still above normal on day 2 (103% of control), but had returned to the normal level by day 8. Measurement of ADC combined with perfusion MRI may help distinguish different subregions in acutely hypoperfused brain.

Aged↗
PubMed2003

Three-dimensional respiratory-gated coronary MR angiography with reference to X-ray coronary angiography.

PURPOSE: To assess the clinical value of three-dimensional coronary MR angiography (CMRA) in the detection of significant coronary artery stenosis using conventional X-ray angiography as the standard reference. MATERIAL AND METHODS: Sixty-nine patients underwent X-ray coronary angiography and CMRA because of suspected or previously diagnosed coronary artery disease. MRI was performed with a 1.5-T whole body imaging system using ECG-triggered 3D gradient echo sequence with retrospective navigator echo respiratory gating and fat suppression. RESULTS: A total of 276 coronary artery segments were analyzed. The X-ray coronary angiography was normal in 22 patients. Significant proximal stenoses (exceeding 50%) or occlusions were present in 102 coronary artery segments. In all, 120 stenoses or occlusions were identified in CMRA. Sixteen percent of the coronary artery segments had to be excluded because of poor image quality. The overall sensitivity and specificity for MRA for identification of significant stenosis were 75% and 62%, respectively. CMRA correctly detected 89% of patients with at least one vessel disease, but 6 patients with coronary artery disease would have been missed. CONCLUSIONS: Because of the high data exclusion and false- negative case rate, CMRA with retrospective navigator echo triggering is at present not suitable as a clinical screening method in coronary artery disease.

Adult↗
PubMed2002

Segmental lumbar spine instability at flexion-extension radiography can be predicted by conventional radiography.

AIM: To identify plain radiographic findings that predict segmental lumbar spine instability as shown by functional flexion-extension radiography. MATERIALS AND METHODS: Plain radiographs and flexion-extension radiographs of 215 patients with clinically suspected lumbar spine instability were analysed. Instability was classified into anterior or posterior sliding instability. The registered plain radiographic findings were traction spur, spondylarthrosis, arthrosis of facet joints, disc degeneration, retrolisthesis, degenerative spondylolisthesis, spondylolytic spondylolisthesis and vacuum phenomena. Factors reaching statistical significance in univariate analyses (P < 0.05) were included in stepwise multiple logistic regression analysis. RESULTS: Degenerative spondylolisthesis (P = 0.004 at L3-4 level and P = 0.017 at L4-5 level in univariate analysis and odds ratio 16.92 at L4-5 level in multiple logistic regression analyses) and spondylolytic spondylolisthesis (P = 0.003 at L5-S1 level in univariate analyses) were the strongest independent determinants of anterior sliding instability. Retrolisthesis (odds ratio 10.97), traction spur (odds ratio 4.45) and spondylarthrosis (odds ratio 3.20) at L3-4 level were statistically significant determinants of posterior sliding instability in multivariate analysis. CONCLUSION: Sliding instability is strongly associated with various plain radiographic findings. In mechanical back pain, functional flexion-extension radiographs should be limited to situations when symptoms are not explained by findings of plain radiographs and/or when they are likely to alter therapy.

Adolescent↗
PubMed2001

WWW--an effective way of teaching radiology.

The Internet and especially the World Wide Web (WWW) have given new opportunities and challenges in teaching radiology. In Kuopio University and Kuopio University Hospital, we started to develop a new WWW-based radiology teaching file in 1996. Our file was made as a result of weaknesses in other files and as an answer to our local needs. The file consists of 1245 separate radiographs in 14 different categories. The language is Finnish, because the target use primarily is basic medical education in Finland. A small part has been translated into English. The quality of images was improved using a separate viewer (Osiris, Digital Imaging Unit, University Hospital of Geneva, Switzerland), which also allowed image manipulation needed with radiological images. We have monitored the utilisation of pages (Analog 1.92 beta-3.0/UNIX) and found the results encouraging. The follow-up time was 814 days (10 February 1997-27 September 1999), the total number of requests was 762797 and that for HTML pages is 288664. Monthly means are 27243 and 10309, respectively. The total number for visited domains is 61. The URL for these pages is http://www.uku.fi/laitokset/klrad/opetuskuvasto/.

Humans↗
PubMed2001

General practitioners' willingness to request plain lumbar spine radiographic examinations.

OBJECTIVES: To examine general practitioners' attitudes to plain lumbar spine radiographic examinations. DESIGN: A postal questionnaire consisting of questions on background data and doctors' opinions about plain lumbar spine radiographic examinations, as well as eight vignettes (imaginary patient cases) presenting indications for lumbar radiography, and five vignettes focusing on the doctors' willingness to request lumbar radiography on the basis of patients' age and duration of symptoms. The data were analysed according to the doctor's age, sex, workplace and the medical school of graduation. SETTING: Finland. SUBJECTS: Six hundred and fifteen randomly selected physicians working in primary health care (64% of original target group). RESULTS: The vignettes revealed that the use of plain lumbar radiographic examination varied between 26 and 88%. Patient's age and radiation protection were the most prominent factors influencing doctors' decisions to request lumbar radiographies. Only slight differences were observed between the attitudes of male and female doctors, as well as between young and older doctors. Doctors' willingness to request lumbar radiographies increased with the patient's age in most vignettes. The duration of patients' symptoms had a dramatic effect on the doctor's decision: in all vignettes, doctors were more likely to request lumbar radiography when patient's symptoms had exceeded 4 weeks. CONCLUSIONS: General practitioners commonly use plain lumbar spine radiographic examinations, despite its limited value in the diagnosis of low back pain. Further consensus and medical education is needed to clarify the indications for plain lumbar radiographic examination.

Adult↗
PubMed2000

Prospective trial of infrapopliteal artery balloon angioplasty for critical limb ischemia: angiographic and clinical results.

PURPOSE: To evaluate the safety and efficacy of infrapopliteal percutaneous transluminal angioplasty (PTA) as a primary treatment of chronic critical limb ischemia in a prospective trial. MATERIALS AND METHODS: Infrapopliteal PTA was performed on 72 limbs of 60 patients (mean age, 72 y; range, 38-92 y) and patients were followed for 12-24 months. RESULTS: The primary angiographic success rate for the stenoses was 84% (102 of 121) and that for the occlusions was 61% (41 of 67) with corresponding restenosis rates of 32% and 52% at follow-up angiography performed a mean of 10 months after primary PTA. The rate of major complications was 2.8% (access site pseudoaneurysms in two patients). The primary clinical success was 63% (45 of 72). A 48% cumulative primary patency rate, a 56% secondary patency rate, and a 80% cumulative limb salvage rate were registered at 18 months, as determined with use of Kaplan-Meier analysis. Lack of angiographic improvement at the site of the most severe ischemia and renal insufficiency (serum creatinine level > 130 micromol/L) were independent predictors of poorer long-term clinical results, as determined with use of Cox multiple regression analysis. CONCLUSIONS: Infrapopliteal PTA is a feasible primary treatment of chronic critical limb ischemia with moderate primary angiographic and clinical success, a low complication rate, and a cumulative limb salvage rate comparable with surgical techniques.

Adult↗
PubMed2000

Cerebral hemodynamics in human acute ischemic stroke: a study with diffusion- and perfusion-weighted magnetic resonance imaging and SPECT.

Nineteen patients with acute ischemic stroke (<24 hours) underwent diffusion-weighted and perfusion-weighted (PWI) magnetic resonance imaging at the acute stage and 1 week later. Eleven patients also underwent technetium-99m ethyl cysteinate dimer single-photon emission computed tomography (SPECT) at the acute stage. Relative (ischemic vs. contralateral control) cerebral blood flow (relCBF), relative cerebral blood volume, and relative mean transit time were measured in the ischemic core, in the area of infarct growth, and in the eventually viable ischemic tissue on PWI maps. The relCBF was also measured from SPECT. There was a curvilinear relationship between the relCBF measured from PWI and SPECT (r = 0.854; P < 0.001). The tissue proceeding to infarction during the follow-up had significantly lower initial CBF and cerebral blood volume values on PWI maps (P < 0.001) than the eventually viable ischemic tissue had. The best value for discriminating the area of infarct growth from the eventually viable ischemic tissue was 48% for PWI relCBF and 87% for PWI relative cerebral blood volume. Combined diffusion and perfusion-weighted imaging enables one to detect hemodynamically different subregions inside the initial perfusion abnormality. Tissue survival may be different in these subregions and may be predicted.

Acute Disease↗
PubMed2000

Combined perfusion- and diffusion-weighted MR imaging in acute ischemic stroke during the 1st week: a longitudinal study.

PURPOSE: To compare findings with different magnetic resonance (MR) perfusion maps in acute ischemic stroke. MATERIALS AND METHODS: Combined diffusion-weighted (DW) and perfusion-weighted (PW) MR imaging was performed in 49 patients with acute (<24 hours) stroke, on the 1st and 2nd days and 1 week after stroke. Volumes of hypoperfused tissue on maps of relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT) were compared with the volume of infarcted tissue at DW imaging. RESULTS: The mean infarct volume increased from 41 to 65 cm(3) between the 1st and 2nd days (P: <.001; n = 49). On the 1st day, all perfusion maps on average showed hypoperfusion lesions larger than the infarct at DW imaging (P: <.001; n = 49). MTT maps showed significantly (P: <.001) larger hypoperfusion lesions than did rCBF maps, which showed significantly (P: <.001) larger hypoperfusion lesions than did rCBV maps. The sizes of the initial perfusion-diffusion mismatches correlated significantly with the extent of infarct growth (0.479 < r < 0.657; P: </=.001). The hypoperfusion volume on the initial rCBV maps correlated best with the final infarct size at 1 week (r = 0.891; P: <.001). CONCLUSION: Combined DW and PW imaging is a powerful tool in evaluating the hemodynamics of acute ischemic stroke.

Acute Disease↗
PubMed1997

Pleural signs of small peripheral pulmonary masses: pathologic correlation with chest radiographs and diagnostic value.

OBJECTIVE: The current interest in 'cost-effectiveness' of medical imagings means that chest radiography is the primary radiological examination of lung diseases. We attempted to investigate the pathological basis of different pleural signs, and determine their usefulness in differentiating small bronchogenic carcinomas from tuberculomas by using chest radiographs. MATERIALS AND METHODS: We prospectively studied 30 small solitary pulmonary masses, including 24 carcinomas and 6 tuberculomas. All 30 resected lobe specimens were investigated with preoperative radiographs, postoperative specimen radiographs, 10-15 microns thick whole-mount sections, and 5 microns thick slices for conventional histological examination. To evaluate the clinical usefulness of these pleural signs, we also retrospectively reviewed 100 chest radiographs and conventional tomographs of 1-3 cm peripheral pulmonary lesions, including 60 bronchogenic carcinomas and 40 tuberculomas. RESULTS: The results confirmed that, besides the previously known interlobular septal fibrosis with pleural retraction, the pathologic basis also included the pleural puckering and adhesion with fluid collection for the 'tail' and 'rabbit ears' signs, and pleural dimpling with fluid collection and peripheral fibrous hyperplasia for the 'triangular shadow' signs. In the retrospective group, the pleural signs with adjacent pleural thickening was significantly more frequent in tuberculomas than in carcinomas (P < 0.05, chi 2-test). CONCLUSION: Pleural signs associated with adjacent pleural thickening seems to contribute to differentiating granulomas from carcinomas. The pathological basis for this radiological finding includes visceral pleural fibrosis with the inflammatory cell infiltration, and the wide and shallow pleural dimpling filled with reactive pleural fluid.

Carcinoma, Bronchogenic↗
PubMed1996

Application of whole-mount section of lung specimen in study of radiologic-pathologic correlations.

We evaluated the usefulness of the whole-mount section of the inflated-fixed lung specimen in the study of radiologic-pathologic correlations. Altogether, 24 resected fresh lobe specimens with 1.5- to 3.0-cm solitary pulmonary carcinomas or tuberculomas were inflated with air, intrabronchially fixed by infusing Heitzman's solution, and finally cut into 10- to 15-micron-thick whole-mount sections for the histopathological examination. All 24 inflated-fixed lobes were satisfactorily soft as sponge, sufficiently springy, and kept their original shape. All whole-mount sections clearly presented the complete morphological features of the whole lobes, and could be directly observed by the naked eye and examined under microscopy. The use of the whole-mount section of the lung specimen may facilitate precisely and effectively the studies of the radiologic-pathologic correlations.

Adenocarcinoma↗
PubMed1996

Pulmonary parenchymal manifestations surrounding small peripheral masses: pathologic correlation with chest radiographs and diagnostic value.

RATIONALE AND OBJECTIVES: We evaluated pathologic correlations of pulmonary parenchymal manifestations surrounding small peripheral masses and their usefulness in differentiating small peripheral bronchogenic carcinomas from tuberculomas. METHODS: We evaluated 29 resected lobe specimens with 1.5- to 3.5-cm solitary pulmonary masses, including 24 carcinomas and five tuberculomas. These specimens were prospectively studied with preoperative chest radiographs, postoperative specimen radiographs, 10- to 15-microns-thick wholemount sections, and 5-microns-thick slices. A total of 100 chest X-rays and conventional tomography scans of 1- to 3-cm peripheral pulmonary masses, including 60 carcinomas and 40 tuberculomas, were retrospectively reviewed and analyzed. RESULTS: The pulmonary parenchymal manifestations surrounding the masses presented as small infiltrates and nodular protrusions, thickened strands, and "double track" shadows, which extended from the proximal margin of five tuberculomas (100%, 5 of 5) and from the distal margin of 17 carcinomas (71%, 17 of 24). These pulmonary changes represented caseous material spreading from tuberculomas into the proximal bronchus and alveolar inflammatory exudation distal to the carcinomas. The proximal pulmonary manifestations were significantly more frequent in tuberculomas than in carcinomas (p < .01), whereas the distal pulmonary manifestations were more often found in carcinomas than in tuberculomas (p < .01). CONCLUSION: The radiologic findings of the pulmonary parenchymal manifestations proximal or distal to the masses may be valuable radiologic signs for distinguishing between tuberculomas and small peripheral bronchogenic carcinomas, even though there is still considerable crossover between the two disease populations in the findings.

Carcinoma, Bronchogenic↗